This 18-200mm F3.5-6.3 DC OS (Optical Stabilizer) high power zoom ratio lens is exclusively designed for digital SLR cameras and is capable of covering a wide range of focal lengths from wide angle to telephoto. It is equipped with Sigma's own unique technology of OS (Optical Stabilizer) function. This function uses two sensors inside the lens to detect vertical and horizontal movement of the camera and works by moving an optical image stabilizing lens group, to effectively compensate for camera shake. It automatically detects movement of the camera and compensates for camera shake when shooting moving subject such as motor sports. Two SLD (Special Low Dispersion) glass elements and three aspherical lenses provide excellent correction for all types of aberrations. The super multi-layer lens coating reduces flare and ghost. This lens provides superior image quality throughout the entire zoom range. An inner focusing system eliminates front lens rotation, making the lens particularly suitable for using circular polarizing filters and the petal-type lens hood supplied.
The Sigma 18-200mm high-zoom-ratio lens is designed exclusively for Sigma digital SLR cameras and is capable of covering a wide range of focal lengths, from wide-angle to telephoto. Two Special Low Dispersion (SLD) glass elements and two hybrid aspherical lenses correct for all types of aberrations, letting Sigma house the extended-range super-zoom lens in a compact and lightweight body that measures 70mm in diameter and 78.1mm long and weighs a mere 14.3 ounces. The new lens coating, meanwhile, reduces flare and ghost--a common problem shared by many digital cameras--while also creating an optimum color balance. Other details include a minimum focusing distance of 45cm (17.7) at all focal lengths, a high zoom ratio of 11:1, and a maximum magnification of 1:4.4.
The lens design incorporates an inner focusing system that prevents the front of the lens from rotating, making it particularly suitable for using circular polarizing filters and petal-shaped lens hoods. In addition, the overall length of the lens never changes during focusing, making the lens convenient to handle and easy to use. Finally, the lens's zoom lock switch eliminates "zoom creep" during transport--a convenient addition when traveling. The lens, which includes a metal mount, is backed by a one-year warranty.